JPS59180853A - Optimum distribution method of cartridge - Google Patents

Abstract

PURPOSE:To improve the efficiency of a large capacity memory system by counting the using frequencies of cartridges, and storing cartridges of high using frequencies into a cell set near a data recorder and the cartridges of low using frequencies into a cell distance away from the data recorder. CONSTITUTION:For a cartridge control program 13, a cartridge optimum distribution function program 15 selects an entry E having the smallest value of a time column and showing an idle state out of a cartridge control table 14 in case a request given from an upper device is equal to a cartridge application request. Then a cartridge identifier is written, and at the same time the value of a cell address column is informed to the program 13. The program 13 sends the cell address and the application request to a cartridge access program, and the applied cartridge is stored into a selected cell. Thus it is possible to reduce the time needed for read/write of cartridges of high using frequencies. In such a way, the using efficiency of a large capacity memory system is improved.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a mass storage system having a plurality of cartridges, a cartridge storage mechanism having a plurality of cells, an access mechanism, and a data recording device. , relates to a method for optimally arranging a cartridge so that it is arranged near a data storage device.

[Prior art and problems]

FIG. 1 is a diagram illustrating an overview of a cartridge storage mechanism, and FIG. 2 is an electrical circuit diagram of a mass storage system (MS S ). In Figures 1 and 2, 1 is car) IJ
2 is a cell; 3 is a cartridge; 4 is a data recording device; 5 is a cartridge input port; 6 is a cartridge discharge port; 7 is a mass storage controller; 8 is an access control device; 9 is an access mechanism; 10 is a staging disk controller, 11 is a data recording controller, 12 is a DAS
D is shown respectively.

The cartridge storage mechanism 1 has a plurality of cells 2, and a cartridge is housed in each cell. 1st
Although only two cells 2 are shown in the figure, there are actually many cells. A data recording device 4 is arranged within the cartridge storage mechanism 1. The data recording device 4 writes data to the cartridge 3,
It is used to read data from the cartridge 3.

The cartridge storage mechanism 1 is provided with a cartridge inlet 5 for inserting the cartridge 3 and a cartridge outlet 6 for discharging the cartridge 3.

The cartridge 3 inserted through the cartridge input port 5 is carried by an access mechanism (not shown) and inserted into the cell 2.

When the cartridge 3 is to be ejected, the cartridge 3 is removed from the cell 2 by the access mechanism, transported to the cartridge ejection port 6, and then ejected from the cartridge ejection port 6.

FIG. 2 is an electrical circuit diagram of the mass storage system. The mass storage controller 7 is a processor that controls the entire mass storage system. The access control device 8 controls the access mechanism 9 according to instructions from the mass storage device 7. The staging disk control device 10 includes:
It controls the DASD 12 as well as the data recording control device 11. The data recording control device 11 controls data transfer between the data recording device 4 and the staging disk control device 100.

It takes a considerable amount of time to remove the cartridge from the cell 2 and insert it into the data recording device 4, but if you place frequently used cartridges far away from the data recording device 4, you can store them in large capacity. The efficiency of the system will decrease. In the prior art, no particular consideration was given to the placement of cartridges within the cartridge storage mechanism.

[Purpose of the invention]

The present invention is based on the above considerations and aims to provide an optimal cartridge placement method for locating cartridges so as to improve the efficiency of a mass storage system.

[Structure of the invention]

Therefore, the optimal cartridge placement method of the present invention provides a cartridge storage mechanism having a plurality of cartridges and a plurality of cells for storing the cartridges, and the cartridge storage mechanism (IJ).
In a mass storage system comprising a data recording device disposed in a storage mechanism, the frequency of use of cartridges is counted, and frequently used cartridges are stored in cells located near the data recording device; The present invention is characterized in that cartridges that are used infrequently are stored in a cell located at a remote location from the data recording device.

[Embodiments of the invention]

Hereinafter, the present invention will be explained with reference to the drawings.

FIG. 3 is a diagram explaining the software configuration for implementing the present invention, FIG. 4 is a diagram showing the configuration of a cartridge management table used in the present invention, and FIG. 5 is a diagram illustrating the processing by the software configuration of FIG. It is a diagram showing a flow.

In order to carry out the present invention, it is necessary to store a cartridge management program 13 in the main memory (not shown) of the mass storage controller 7.
A cartridge management table 14 and a cartridge optimum placement function program 15 are stored. The cartridge management program 13 is for managing cartridges based on the cartridge management table 14, and the optimal cartridge placement function program 15 is for optimal placement of cartridges. FIG. 4 shows the structure of the cartridge management table 14. The cartridge management table 14 has a plurality of entries E, and each entry E has a cartridge identifier field, a cell address field,
It has a time column, a recent use date column, and a use frequency column. One entry E is assigned to one cell, and the cartridge identifier column contains the identifier (serial number of the cartridge) of the cartridge stored in that cell.
is filled in, the cell address field is filled in with the address assigned to that cell, the time field is filled in with the time it takes for the cartridge to travel between that cell and the data storage device, and the most recently used date field is filled in. The date when the cartridge stored in that cell was most recently used is entered in the field, and the usage frequency of the cartridge stored in that cell is entered in the usage frequency column. The values in the cell address field and the time field are uniquely determined by the physical structure of the cartridge storage mechanism 1, and these values are never rewritten. When N data recording devices 4 exist in the cartridge storage mechanism 1, the value T in the time column is determined as follows.

where ti is the time required for the cartridge to move between that cell and the second data storage device. The end IJEs of the cartridge management table 14 are arranged so that the smaller the value in the time column is, the earlier the end IJE is.

FIG. 5 shows the flow of processing by the software in FIG. 3.

When a request is sent from a host device, the cartridge management program 13 issues a cartridge input request, cartridge ejection request, cartridge optimal placement request, or other (
Check whether the cartridge has fallen during the cartridge movement process.

If it is a cartridge input request, the cartridge optimum placement function program 15 is executed. The optimal cartridge placement program 13 selects the entry E that has the smallest value in the time field and is empty in the cartridge management table 14, and writes the cartridge identifier into the selected entry E. At the same time, the cartridge management program 13 is notified of the value in the cell address column of the selected entry. Cartridge management program 13 passes this cell address and input request to a cartridge access program (not shown).

The cartridge inserted by this cartridge Φ access program is stored in the selected cell.

In the case of a cartridge ejection request, the cartridge optimum placement function program 15 searches for the entry E corresponding to the cartridge to be ejected, and clears all other fields in this entry E except for the cell 1 address field and time field. At the same time, the value in the cell 1 address column of the entry E is notified to the cartridge management program 13. The cartridge management program 13 passes this cell address and ejection request to the cartridge access program, and the cartridge to be ejected is taken out from the cell and ejected under the control of the cartridge access program.

In the case of a cartridge optimum placement request, the cartridge optimum placement function program 15 reads all entry data from the cartridge management table 14, and creates a list of entry data with a frequency of use of 5 times or less, a list of entry data with a usage frequency of 5 times or less, a list of entry data with a usage frequency of 6 to 10 times, etc. A list of entry data with usage frequency and a list of entry data with usage frequency of 11 or more times are created. At this time, entry data whose most recently used date column indicates the current day is handled as data that has been used 11 times or more. Then, the list of entry data having a usage frequency of 5 times or less is sorted so that the one with the smallest value in the time column comes first. This is called list L. Similarly, a list of entry data having a frequency of use of 6 to 10 times is also sorted so that the values in the time column are first. This is called list L2. A list of entry data having a frequency of use of 11 times or more is sorted so that the data with the highest frequency of use comes first. This is called list L.

Next, the first entry data in list L; is compared with the first entry data in list L, and if the value in the time column of the former is smaller than the value in the time column of the latter, the cartridge specified in the former is The cartridge management program 13 is notified that the cartridge specified by the latter should be replaced, the leading entry data is deleted from the lists L1 and L3, and the cartridge management table 14 is rewritten. This process is performed when the value of the time column of the first entry data in list L is
This process is repeated until the value in the time field of the first entry data is exceeded.

If the value in the time column of the first entry data in list L is not greater than the value in the time column of the first entry data in list L3, and if there is any entry data left in list L3, then list L2 The cartridge replacement process is performed in the same manner as in comparison with the current cartridge L3. List L3
After all entry data is removed from the cartridge management table 14, the use frequency column and the most recent use date column are cleared.

In the case of cartridge movement processing, the cartridge management program 13 performs processing to move the cartridge to the requesting cell or data recording device, and updates the corresponding enumeration in the cartridge management table 14 with IJE's recent use date information and use. Update frequency information.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the time required to read and write frequently used cartridges can be shortened, thereby improving the usage efficiency of the mass storage system.

[Brief explanation of drawings]

Fig. 1 is a diagram explaining the outline of the cartridge storage mechanism, Fig. 2 is an electric circuit diagram of the mass storage system (MSS), Fig. 3 is a diagram explaining the software configuration for implementing the present invention, and Fig. 4 is a diagram explaining the outline of the cartridge storage mechanism. This figure shows the configuration of a cartridge management table used in the present invention, and FIG. 5 is a diagram showing the flow of processing by the software configuration of FIG. 3. 1... Cartridge storage mechanism, 2... Cell, 3...
・Cartridge, 4...Data recording device, 5...Cartridge inlet, 6...Cartridge outlet, 7.
... Mass storage control device, 8... Access control device,
9... Access mechanism, 10... Staging disk control device, 11... Data recording control device, 12.
...DASD0 Patent Applicant Fujitsu Limited Representative Patent Attorney Kyotani Yobuo 1 Figure 2 Figure 3

Claims (1)

[Claims] In a mass storage system comprising a plurality of cartridges, a cartridge storage mechanism having a plurality of cells for storing the cartridges, and a data recording device disposed in the cartridge storage mechanism, the frequency of use of the cartridges is counted and the frequency of use is calculated. An optimal cartridge placement method characterized by storing expensive cartridges in cells located near the data recording device and storing less frequently used cartridges in cells located remote from the data recording device.